The use of optics and optical devices in fields such as communications and computing has created a need for optical devices which increase the power gain of optical signals. Also, the complexity of the processing required in these fields makes it desirable, and even necessary, to exactly replicate optical signals so that these signals can be processed in parallel and without significant power loss.
One technique for increasing the power of an optical signal is to amplify the optical signal using a phototransistor. However, phototransistors require careful manufacturing controls. In particular, it is difficult to obtain an array of phototransistors with gain characteristics within acceptable tolerances for amplifying an entire image at the same amplification characteristics.
Replicas of optical signals can be created using beam splitters. However, beam splitters often are less than perfectly manufactured and thus may create unequal reflected and transmitted images. Moreover, use of a beam splitter to create a replica of an optical signal reduces the power of the created replicas because the power in the original signal is divided among the replicas. This reduced power may be insufficient to allow high-speed parallel processing of the optical signals.